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Speed of light is the highest possible speed

  1. Dec 26, 2004 #1
    the speed of each wavelenght of EM is different so the energy of the particles also differ.

    Now i have a doubt. the speed of light is the highest possible speed. if the above given statement is true the the speed of gamma waves is greater???? :confused:
     
  2. jcsd
  3. Dec 26, 2004 #2

    dextercioby

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    My friend,u missunderstood a great deal of physics.The fundamental relation for the electromagnetic radiation in vacuum states that
    [tex]c=\lambda\nu [/tex]
    ,where [itex] \lambda [/itex] is the wavelength,and [itex] \nu [/itex] is the frequency.In vacuo,the speed of the propagation of EM waves is "c" and is constant,regarding of any other characteristics of the wave.The radio waves and the gamma waves have all the same speed of propagation as the visible radiation (which,out of convenience and habit we still call "light"),namely "c".These waves distinguish each other through their frequency and wavelength.Since the product of these 2 quantities is constant,it means the greater one,the smaller the other for the same wave.
    The energies of each wave (or iyou prefer photon) are different,but their speed is the same,sice some photons are "easier" than other.They have a relativistic mass greater/smaller.
    Such discussions are based on the following formulae:
    [tex] E_{photon}=h\nu_{photon}=m_{photon}c^{2} [/tex]

    I advise u to read a text on em.or optics very,very carefully.

    Daniel.
     
  4. Dec 27, 2004 #3
    One thing is wierd regarding light.
    How come light wave is two-dimentional?!
    Is it just a way (one of many) for scientist to comprehand things in order to represent them more down-to-Earth, and use them more easily in representations of different phenomena ( - the matter of practise), or is it really the truth (e.i. the way photons (particles?) actually move)?
    I mean: when you fire-away some high velocity object (a bullet) for example - then the smoke (or is it actually air?) behind it goes spiral, and when you look at it from a side it really looks like a 2D wave (heaven forbid - seeing it as a spiraling circle from the front! :smile: ).

    Isn't a similar thing possible with photons? (having in mind that now it seems that even Space itself isn't actually empty, but it consists of the VERY primar building blocks of all the matter ( - both substances and fields); maybe Space is to the photon likewhat air is to the bullet)

    But then - how to explain polarisation? (so-called "planar characteristic of lightwave")

    Where does this theory of light as a two-dimentional wave come from? Why?

    ...Or isn't it just possible that photon is a particle (or one that consists of two (quark,anti-quark)) that rotates around itself - so there is no wave in space, just rotation within the particle (and that's its energy and frequency).

    Then: if photon is a particle, where does it come from? Matter cannot be created, it only circulates and changes its shape - does it mean that light-emmiting objects lose their weight? Or maybe the space itself consist of some primar particles, which recombine and shoot-away as (newly constructed) photons when they come in contact with excited particles of substance (subatomic particles - electrons/protons)... Maybe then light degrades (after it reaches certain distance in Space), and decomposes into those primar particles of Space (or it diverges into some kind of "well" (a point in space where matter becomes Space (again) - (maybe even a black "hole(s)"?!?!?)) to be deconstructed), so they are (kind-of) recycled to be used again. I mean: where does all of this light go?! It cannot just dissapear - everything circulates.
    Is it possible that every quantum particle consists of (certain number of) primar particles of Space (then it would mean that that particle is The LOGOS itself, because all logic (in all branches of physics) comes (basicaly) from it!?

    Further more does force called gravity actually come from "Space weght" (pressure) on matter (e.g. huge matter - like Earth), rather then the other way around (that the gravity force come inside-out of matter)? (Sort-of like deep sea pressure on objects in it)

    ...

    I'm really not into all these things, but - how come scientist do not propagate their advanced discoveries about quantum particles using television media so all peple could know more about these things(?), not just those who study it?
     
  5. Dec 27, 2004 #4

    HallsofIvy

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    Wow! Where to start???

    "the speed of each wavelenght of EM is different so the energy of the particles also differ."

    NO!! the speed of each wavelength is exactly the same: c in vacuum. The energy of the photons depends upon frequency (and so wavelength) not speed.

    "How come light wave is two-dimentional?! "

    Where did you get the idea that it is? A "light wave" is a three dimensional wave front. Of course, if you are standing looking at the light, the wave-front, as it passes by you, will appear to be a plane, just as water waves appear linear.

    "if photon is a particle, where does it come from? Matter cannot be created, it only circulates and changes its shape -"

    Yes, it can be created: E= mc2. Energy and matter are different versions of the same thing. After relativity there is no "conservation of matter" or "conservation of energy" law, only "conservation of energy" but conservation of "matter-energy". By the way, while the photon is a particle, it has no mass.
     
  6. Dec 29, 2004 #5

    Why do you mix my post with his? Besides - his is already answered.
    (of course speed of light is constant; energy/frequency is completely different thing)

    I (on the other hand) asked why do scientist represent light as a wave? Of course it is in three-dimentional world - but I ask: why do scientist think that photon moves in that zig-zag way. My point was: maybe it is a spiral, or there is spinning only inside a particle (photon), so there is no moving up and down. I asked if that was: just an easy way to graphicaly represent light vawelenght - not the way it really happens in nature.

    Light exists, therefore there mus be bearer of it - photon - a particle; and if it exists, then it means that it occupies some space, and it occupies some space, than it changes its properies - e.i. weight - e.i. photon has a weight (but it is so small that it is not important). Matter cannot be created out of nothing, there must be some resource, some raw material to make it - the same is with photon (maybe it is a combination of Space particle - the raw material is all-around).
     
  7. Dec 29, 2004 #6
    SAZAR, if you're referring to diagrams such as this, then I think you're taking things a little bit too litterally. This is just a 2D representation of how a light wave behaves. More specifically, it is a plot of the strength of the electric or magntic field that are associated with light, and not the path of a photon.

    As you may know, light is an electro-magnetic wave. It propagates via the interacting oscillations of the electric and magnetic fields. A change in the electric field produces a change in the magnetic field, which in turn produces a change in the electric field, and so on. The two fields are always perpindicular to each other, as well as to the direction of travel. See here.
     
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